I think some of things you mentioned were explained or not that relevant to the main plot line and could be explained in a side story.
First the the whole elf race was eliminated by Kalix’s shadows, and he didn’t kiss her because love but as they explained it’s a form of a blessing to protect/heal Rose, for the dessert princess personally I believe she wasn’t relevant to main plot since what was happening is much bigger than she could handle what they agreed on is Kalix making her an empress then she will support him through a normal struggle to get the throne and if the author decides to expand on her story it’d probably be on a side story, the duke died with the first prince they tried to poison Kalix after/during the emperor funeral, last for the dragon and this is my personal interpretation I don’t think he was in love at least in the romantic sense with Rose he was more like a toddler clinging to his toy, he was bored and lonely and Rose was someone different someone he couldn’t control so it sparked his curiosity did he care about her? Absolutely but as I said he was like toddler he didn’t know how to express his feelings properly so it came in as possessiveness.
I hope this explains everything and excuse me if there’s any mistakes Eng isn’t my first language
Well explained
I think there's a lot of plot holes. The story's really good that I've read it in just a day from morning to night, but there are just some things that are not detailed enough for me. Like what happened to that handsome white-haired elf? Like, I expected that he'll have a bit more screen time bcs he kissed the fl. What happened to the woman (who is supposed to win over the throne) in Desset (i forgot the place) because they don't allow magic? Like, did she succeed? Also, they kept mentioning that the duke's evil, but I don't think I've seen his face nor how he fought all throughout the chapters (correct me if I'm wrong). They just kept on mentioning how evil he is and how he tortured the Crown prince at that time, also, Aaron even went far as putting a chain in the Crown prince's heart at that time for the FL, so why did he just let it all go and started acting normally? I would also like to add how the story did not tell what happened to the green-haired guy who was obsessed with the otherworldly girl.
I was so freakin flabbergasted when the plot twist just kept on going that I can't help but rant it out. These male characters are all just obsessed freaks. Like fr. LASTLY, WHY DO THEY MAKE ALL THE SUPPOSEDLY VILLAINS GOOD LOOKING THAT I THOUGHT THEY ARE GOOD Like what a waste :(